mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless/transparent; Luster: Vitreous; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Colorless/transparent
Luster: Vitreous

Identified May 22, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless/transparent; Luster: Vitreous; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Forms in igneous, metamorphic, and sedimentary environments, primarily through hydrothermal activity and the cooling of silica-rich magma or aqueous solutions. Found globally across all geological ages.

Uses & applications

Widely used in electronics (oscillators), optics, glassmaking, abrasives, jewelry (faceting and cabochons), and as spiritual/collector specimens.

Geological facts

Quartz is one of the most abundant minerals in Earth's continental crust. Pure clear quartz is known as 'Rock Crystal' and was historically believed by some cultures to be permanently frozen ice.

Field identification & locations

Identify by its hardness (scratches glass), lack of cleavage, and conchoidal fracture. Commonly found in pegmatites, hydrothermal veins, and as sand grains. Look for hexagonal prism habits when intact.